If you played a text-based adventure game, you've played interactive fiction (IF), a style of game made popular by Infocom. You wander around rooms, picking up and manipulating items to solve puzzles, defeat monsters and so on. The best examples of these games immerse the player in a world so well that the imperfections of the text based interface is forgotten.
Things have come a long way since the 8bit machines that ran those games. Without those early constraints Interactive Fiction games have become more complex, with modern interfaces and games that run in the browser. And, of course, adult interactive fiction (AIF) was inevitable.
One way in which the complexity is increased is to allow the player's character to be more mutable; changing size, sex, growing fatter or thinner, or changing species. These are all of interest when considering games for those interested in plump furries.
An innocent champion is sent to battle a demonic infestation. Do they remain pure, or succumb to the corrupting influcences that alter the character?
Plenty of scope for developing a character that fits your interests. Includes demon, dog, cat, 'taur, naga, shark characters. Frequent updates, and ever more complex options. Subsequently inspired Nimin, and others.
Flash based game that can be played in browser or downloaded.
A man who treats women as sex objects is cursed and must live a new life as a woman.
Includes werewolf, feline, avian, and demon transformations. You will need to give the game time to open up these options as the play is more like a dating-sim.
Windows-only RAGS based game.
In a land of abundance, where people are losing themselves to gluttony and hedonism, you decide there must be something more out there.
Fattening focused game with furry characters.
Flash based in-browser game, or download and play locally. Note that the game is hosted on FurAffinity, and you need to create an account to see adult content. If the link dies start at Noone's user page. The game was in the scraps section at the time of writing.
Emerging from a cold war bunker into a strange mutated world, what must you do to survive?
Includes a vast array of furry species and transformations.
Javascript based in-browser play, or download the "glorb" file play in an IF interpreted of your choice (eg. Windows: winglulxe, OSX: zoom). Flexible Survival is also a multiplayer game, and a book.
Explore the different communities in the world of Nimin.
Cat, Horse, Lizard, Wolf, and Human player characters. Definitely on the furry side. Transformations are more optional than some of the other games here.
Flash based in-browser game, or download and play locally. Note that the game is hosted on FurAffinity, and you need to create an account to see adult content. If the link dies start at Xadrea's user page.
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Decide what you wish to be in the world of Pornarium.
Will you be man, woman, or futa?
Will you transform into a bizarre sexual creature
or will you merely live out a normal life?
Pornarium includes images to go along with the text, and a feature-rich combat system. Transformations include cat and fox forms.
VisualBasic and .Net based windows only install.
These games are in early stages of development, and offer limited gameplay compared with the perpetual-beta games above.
"It started out small. A tail here, eras there. Some of the women began developing a second and third set of breasts."
Currently at an alpha stage of development. Has horse, rabbit, wolf, eagle, goat, and rat forms.
Flash based in-browser game, or download and play locally. Note that the game is linked on FurAffinity, and you need to create an account to see adult content. To find the latest version or if the link dies start at Redraster's user page. The game is in his scraps gallery at the moment.
In another time, in another place, explore the curious city of Naryin.
Currently at an early alpha stage of development. Has dragon, cat, wolf and horse forms. Unfortunately the last update was in May 2011.
Flash based in-browser game, or download and play locally. Note that the game is linked on FurAffinity, and you need to create an account to see adult content. To find the latest version or if the link dies start at Syanus's user page.
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Roam the extensive and varied habitats, foraging
for food, potions, and strange mushrooms.
Currently at an early stage, with only dragon forms.
Java based game to download and play locally. Note that the game is hosted on FurAffinity, and you need to create an account to see adult content. If the link dies start at Vilified's user page.
Discover what has happened to your sibling, and probably get very distracted along the way.
My own contribution to the genre, in an early stage of development.
JavaFX based game to play online or download and play locally.
While not in the same interactive fiction style as the above games, these two games might be of interest, but possibly not furry enough. Both are management style games.
Sim style game with cow girls on a farm. In a very early stage of development, watch that space.
Cow girls, obviously.
Flash based game download and play locally. No longer being developed.
A chef prepares a special meal for his female date.
Not actually a furry game, but interesting as for early body type modification modelling.
Flash based game download and play locally. No longer being developed.
Covers all kinds of interactive fiction.
Board for discussion, announcement and programming of IF games featuring transformation. There's also a Wiki which lists many games. The wiki categories give some good starting points. There are games with transformation into anthros, animals, and mythical creatures.
Covers all kinds of furry games. You need an account on SoFurry to read the group.
Interactive Fiction inspired by Hill House stories.
Lots of furry transformations, M/F etc.
Inform game with interpreter to run in your browser.